dma-direct: rename dma_noop to dma_direct
The trivial direct mapping implementation already does a virtual to
physical translation which isn't strictly a noop, and will soon learn
to do non-direct but linear physical to dma translations through the
device offset and a few small tricks. Rename it to a better fitting
name.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Vladimir Murzin <vladimir.murzin@arm.com>
diff --git a/MAINTAINERS b/MAINTAINERS
index 234e642..2d54e63 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -4334,7 +4334,7 @@
W: http://git.infradead.org/users/hch/dma-mapping.git
S: Supported
F: lib/dma-debug.c
-F: lib/dma-noop.c
+F: lib/dma-direct.c
F: lib/dma-virt.c
F: drivers/base/dma-mapping.c
F: drivers/base/dma-coherent.c
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 00d889a..430a0aa 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -25,7 +25,7 @@
select CLONE_BACKWARDS
select CPU_PM if (SUSPEND || CPU_IDLE)
select DCACHE_WORD_ACCESS if HAVE_EFFICIENT_UNALIGNED_ACCESS
- select DMA_NOOP_OPS if !MMU
+ select DMA_DIRECT_OPS if !MMU
select EDAC_SUPPORT
select EDAC_ATOMIC_SCRUB
select GENERIC_ALLOCATOR
diff --git a/arch/arm/include/asm/dma-mapping.h b/arch/arm/include/asm/dma-mapping.h
index e5d9020..8436f6a 100644
--- a/arch/arm/include/asm/dma-mapping.h
+++ b/arch/arm/include/asm/dma-mapping.h
@@ -18,7 +18,7 @@ extern const struct dma_map_ops arm_coherent_dma_ops;
static inline const struct dma_map_ops *get_arch_dma_ops(struct bus_type *bus)
{
- return IS_ENABLED(CONFIG_MMU) ? &arm_dma_ops : &dma_noop_ops;
+ return IS_ENABLED(CONFIG_MMU) ? &arm_dma_ops : &dma_direct_ops;
}
#ifdef __arch_page_to_dma
diff --git a/arch/arm/mm/dma-mapping-nommu.c b/arch/arm/mm/dma-mapping-nommu.c
index 6db5fc2..4d80425 100644
--- a/arch/arm/mm/dma-mapping-nommu.c
+++ b/arch/arm/mm/dma-mapping-nommu.c
@@ -22,7 +22,7 @@
#include "dma.h"
/*
- * dma_noop_ops is used if
+ * dma_direct_ops is used if
* - MMU/MPU is off
* - cpu is v7m w/o cache support
* - device is coherent
@@ -39,7 +39,7 @@ static void *arm_nommu_dma_alloc(struct device *dev, size_t size,
unsigned long attrs)
{
- const struct dma_map_ops *ops = &dma_noop_ops;
+ const struct dma_map_ops *ops = &dma_direct_ops;
void *ret;
/*
@@ -70,7 +70,7 @@ static void arm_nommu_dma_free(struct device *dev, size_t size,
void *cpu_addr, dma_addr_t dma_addr,
unsigned long attrs)
{
- const struct dma_map_ops *ops = &dma_noop_ops;
+ const struct dma_map_ops *ops = &dma_direct_ops;
if (attrs & DMA_ATTR_NON_CONSISTENT) {
ops->free(dev, size, cpu_addr, dma_addr, attrs);
@@ -213,7 +213,7 @@ EXPORT_SYMBOL(arm_nommu_dma_ops);
static const struct dma_map_ops *arm_nommu_get_dma_map_ops(bool coherent)
{
- return coherent ? &dma_noop_ops : &arm_nommu_dma_ops;
+ return coherent ? &dma_direct_ops : &arm_nommu_dma_ops;
}
void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
diff --git a/arch/m32r/Kconfig b/arch/m32r/Kconfig
index 498398d..dd84ee1 100644
--- a/arch/m32r/Kconfig
+++ b/arch/m32r/Kconfig
@@ -19,7 +19,7 @@
select MODULES_USE_ELF_RELA
select HAVE_DEBUG_STACKOVERFLOW
select CPU_NO_EFFICIENT_FFS
- select DMA_NOOP_OPS
+ select DMA_DIRECT_OPS
select ARCH_NO_COHERENT_DMA_MMAP if !MMU
config SBUS
diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index 2c6adf1..865e14f 100644
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -83,7 +83,7 @@
config HAVE_KPROBES
def_bool n
-config DMA_NOOP_OPS
+config DMA_DIRECT_OPS
def_bool y
menu "Platform type"
diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index 829c679..9376637 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -140,7 +140,7 @@
select HAVE_DEBUG_KMEMLEAK
select HAVE_DMA_API_DEBUG
select HAVE_DMA_CONTIGUOUS
- select DMA_NOOP_OPS
+ select DMA_DIRECT_OPS
select HAVE_DYNAMIC_FTRACE
select HAVE_DYNAMIC_FTRACE_WITH_REGS
select HAVE_EFFICIENT_UNALIGNED_ACCESS
diff --git a/include/asm-generic/dma-mapping.h b/include/asm-generic/dma-mapping.h
index 1640315..880a292 100644
--- a/include/asm-generic/dma-mapping.h
+++ b/include/asm-generic/dma-mapping.h
@@ -4,7 +4,7 @@
static inline const struct dma_map_ops *get_arch_dma_ops(struct bus_type *bus)
{
- return &dma_noop_ops;
+ return &dma_direct_ops;
}
#endif /* _ASM_GENERIC_DMA_MAPPING_H */
diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h
index 46542ad..34fe846 100644
--- a/include/linux/dma-mapping.h
+++ b/include/linux/dma-mapping.h
@@ -136,7 +136,7 @@ struct dma_map_ops {
int is_phys;
};
-extern const struct dma_map_ops dma_noop_ops;
+extern const struct dma_map_ops dma_direct_ops;
extern const struct dma_map_ops dma_virt_ops;
#define DMA_BIT_MASK(n) (((n) == 64) ? ~0ULL : ((1ULL<<(n))-1))
diff --git a/lib/Kconfig b/lib/Kconfig
index c5e84fb..9d3d649 100644
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -409,7 +409,7 @@
depends on !NO_DMA
default y
-config DMA_NOOP_OPS
+config DMA_DIRECT_OPS
bool
depends on HAS_DMA && (!64BIT || ARCH_DMA_ADDR_T_64BIT)
default n
diff --git a/lib/Makefile b/lib/Makefile
index d11c48e..749851a 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -28,7 +28,7 @@
lib-$(CONFIG_MMU) += ioremap.o
lib-$(CONFIG_SMP) += cpumask.o
-lib-$(CONFIG_DMA_NOOP_OPS) += dma-noop.o
+lib-$(CONFIG_DMA_DIRECT_OPS) += dma-direct.o
lib-$(CONFIG_DMA_VIRT_OPS) += dma-virt.o
lib-y += kobject.o klist.o
diff --git a/lib/dma-direct.c b/lib/dma-direct.c
new file mode 100644
index 0000000..0ec3262
--- /dev/null
+++ b/lib/dma-direct.c
@@ -0,0 +1,63 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * lib/dma-noop.c
+ *
+ * DMA operations that map to physical addresses without flushing memory.
+ */
+#include <linux/export.h>
+#include <linux/mm.h>
+#include <linux/dma-mapping.h>
+#include <linux/scatterlist.h>
+#include <linux/pfn.h>
+
+static void *dma_direct_alloc(struct device *dev, size_t size,
+ dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs)
+{
+ void *ret;
+
+ ret = (void *)__get_free_pages(gfp, get_order(size));
+ if (ret)
+ *dma_handle = virt_to_phys(ret) - PFN_PHYS(dev->dma_pfn_offset);
+
+ return ret;
+}
+
+static void dma_direct_free(struct device *dev, size_t size, void *cpu_addr,
+ dma_addr_t dma_addr, unsigned long attrs)
+{
+ free_pages((unsigned long)cpu_addr, get_order(size));
+}
+
+static dma_addr_t dma_direct_map_page(struct device *dev, struct page *page,
+ unsigned long offset, size_t size, enum dma_data_direction dir,
+ unsigned long attrs)
+{
+ return page_to_phys(page) + offset - PFN_PHYS(dev->dma_pfn_offset);
+}
+
+static int dma_direct_map_sg(struct device *dev, struct scatterlist *sgl,
+ int nents, enum dma_data_direction dir, unsigned long attrs)
+{
+ int i;
+ struct scatterlist *sg;
+
+ for_each_sg(sgl, sg, nents, i) {
+ dma_addr_t offset = PFN_PHYS(dev->dma_pfn_offset);
+ void *va;
+
+ BUG_ON(!sg_page(sg));
+ va = sg_virt(sg);
+ sg_dma_address(sg) = (dma_addr_t)virt_to_phys(va) - offset;
+ sg_dma_len(sg) = sg->length;
+ }
+
+ return nents;
+}
+
+const struct dma_map_ops dma_direct_ops = {
+ .alloc = dma_direct_alloc,
+ .free = dma_direct_free,
+ .map_page = dma_direct_map_page,
+ .map_sg = dma_direct_map_sg,
+};
+EXPORT_SYMBOL(dma_direct_ops);
diff --git a/lib/dma-noop.c b/lib/dma-noop.c
deleted file mode 100644
index a10185b..0000000
--- a/lib/dma-noop.c
+++ /dev/null
@@ -1,68 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * lib/dma-noop.c
- *
- * DMA operations that map to physical addresses without flushing memory.
- */
-#include <linux/export.h>
-#include <linux/mm.h>
-#include <linux/dma-mapping.h>
-#include <linux/scatterlist.h>
-#include <linux/pfn.h>
-
-static void *dma_noop_alloc(struct device *dev, size_t size,
- dma_addr_t *dma_handle, gfp_t gfp,
- unsigned long attrs)
-{
- void *ret;
-
- ret = (void *)__get_free_pages(gfp, get_order(size));
- if (ret)
- *dma_handle = virt_to_phys(ret) - PFN_PHYS(dev->dma_pfn_offset);
-
- return ret;
-}
-
-static void dma_noop_free(struct device *dev, size_t size,
- void *cpu_addr, dma_addr_t dma_addr,
- unsigned long attrs)
-{
- free_pages((unsigned long)cpu_addr, get_order(size));
-}
-
-static dma_addr_t dma_noop_map_page(struct device *dev, struct page *page,
- unsigned long offset, size_t size,
- enum dma_data_direction dir,
- unsigned long attrs)
-{
- return page_to_phys(page) + offset - PFN_PHYS(dev->dma_pfn_offset);
-}
-
-static int dma_noop_map_sg(struct device *dev, struct scatterlist *sgl, int nents,
- enum dma_data_direction dir,
- unsigned long attrs)
-{
- int i;
- struct scatterlist *sg;
-
- for_each_sg(sgl, sg, nents, i) {
- dma_addr_t offset = PFN_PHYS(dev->dma_pfn_offset);
- void *va;
-
- BUG_ON(!sg_page(sg));
- va = sg_virt(sg);
- sg_dma_address(sg) = (dma_addr_t)virt_to_phys(va) - offset;
- sg_dma_len(sg) = sg->length;
- }
-
- return nents;
-}
-
-const struct dma_map_ops dma_noop_ops = {
- .alloc = dma_noop_alloc,
- .free = dma_noop_free,
- .map_page = dma_noop_map_page,
- .map_sg = dma_noop_map_sg,
-};
-
-EXPORT_SYMBOL(dma_noop_ops);